{"id":4719,"date":"2026-10-08T09:31:45","date_gmt":"2026-10-08T09:31:45","guid":{"rendered":"https:\/\/www.tomat-pomidor.com\/en\/?p=4719"},"modified":"2026-10-10T19:59:10","modified_gmt":"2026-10-10T19:59:10","slug":"brown-tomato-leaf-spots-debate","status":"publish","type":"post","link":"https:\/\/www.tomat-pomidor.com\/en\/brown-tomato-leaf-spots-debate\/","title":{"rendered":"Brown Tomato Leaf Spots: Fungal Disease vs. Deficiency | Growers Debate"},"content":{"rendered":"\n\n<div class=\"kk-star-ratings kksr-auto kksr-align-left kksr-valign-top\"\n    data-payload='{&quot;align&quot;:&quot;left&quot;,&quot;id&quot;:&quot;4719&quot;,&quot;slug&quot;:&quot;default&quot;,&quot;valign&quot;:&quot;top&quot;,&quot;ignore&quot;:&quot;&quot;,&quot;reference&quot;:&quot;auto&quot;,&quot;class&quot;:&quot;&quot;,&quot;count&quot;:&quot;0&quot;,&quot;legendonly&quot;:&quot;&quot;,&quot;readonly&quot;:&quot;&quot;,&quot;score&quot;:&quot;0&quot;,&quot;starsonly&quot;:&quot;&quot;,&quot;best&quot;:&quot;5&quot;,&quot;gap&quot;:&quot;5&quot;,&quot;greet&quot;:&quot;Rate this&quot;,&quot;legend&quot;:&quot;0\\\/5 - (0 votes)&quot;,&quot;size&quot;:&quot;24&quot;,&quot;title&quot;:&quot;Brown Tomato Leaf Spots: Fungal Disease vs. Deficiency | Growers Debate&quot;,&quot;width&quot;:&quot;0&quot;,&quot;_legend&quot;:&quot;{score}\\\/{best} - ({count} {votes})&quot;,&quot;font_factor&quot;:&quot;1.25&quot;}'>\n            \n<div class=\"kksr-stars\">\n    \n<div class=\"kksr-stars-inactive\">\n            <div class=\"kksr-star\" data-star=\"1\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"2\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"3\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"4\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" data-star=\"5\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n    <\/div>\n    \n<div class=\"kksr-stars-active\" style=\"width: 0px;\">\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n            <div class=\"kksr-star\" style=\"padding-right: 5px\">\n            \n\n<div class=\"kksr-icon\" style=\"width: 24px; height: 24px;\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n                \n\n<div class=\"kksr-legend\" style=\"font-size: 19.2px;\">\n            <span class=\"kksr-muted\">Rate this<\/span>\n    <\/div>\n    <\/div>\n<div class=\"tldr-box\" style=\"background: #f4f9f4; padding: 20px; border-left: 5px solid #4CAF50; margin-bottom: 30px; border-radius: 4px;\">\n<h3>\ud83d\udccc Quick Summary: The Tomato Blight Debate<\/h3>\n<ul>\n<li>\ud83c\udf45 <strong>The Standard Advice:<\/strong> When tomato leaves develop yellow halos and dry brown spots, most gardening books say it is a fungal disease (like Early Blight or Anthracnose) and you must reach for fungicides immediately.<\/li>\n<li>\ud83e\udd76 <strong>Our Community&#8217;s Insight:<\/strong> Veteran growers from cold climates (Zone 3 and 4) noticed something different. These fungal infections almost always start as <em>Chlorosis<\/em> (a micronutrient deficiency). But the lack of nutrients isn&#8217;t because the soil is poor, it&#8217;s because <strong>cold spring soil<\/strong> and planting out too early severely stunt the root system.<\/li>\n<li>\ud83e\uddea <strong>The Verdict?<\/strong> Before you spray harsh chemicals on your tomatoes, read the discussion below. Learn how the leaves actually control root growth, and why a simple Iron Chelate foliar spray (feeding through the leaves) might be the first step to saving a stressed plant.<\/li>\n<\/ul>\n<\/div>\n<div class=\"add-review-cta\" style=\"margin: 20px 0; padding: 15px; background: #f9f9f9; border-left: 4px solid #4CAF50; border-radius: 4px;\"><strong>\ud83d\udcac Do you transplant your tomatoes into cold soil?<\/strong> <a href=\"#wpdcom\">Tell us how you prevent leaf spots below!<\/a><\/div>\n<div class=\"forum-post\">\n<div class=\"author-header\">\n<div class=\"forum-avatar\" style=\"background-color: #e91e63; color: white; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 15px; font-size: 1.2em;\">S<\/div>\n<div class=\"author-meta\">\n<div class=\"author-name\">Svetlana-Kr <span class=\"author-stats\">\u2b50 Pro Grower (1,952 posts)<\/span><\/div>\n<div class=\"author-geo\">\ud83d\udccd Zvenigorod, Moscow Reg. (USDA Zone 4b) | \ud83d\udcc5 July 26, 2021<\/div>\n<\/div>\n<\/div>\n<div class=\"post-content\">\n<p>Luda, is this Early Blight (Macrosporiosis) or what? It&#8217;s literally giving me nightmares&#8230;<\/p>\n<p><img decoding=\"async\" style=\"max-width: 100%; height: auto; border-radius: 5px; margin: 10px 0;\" src=\"https:\/\/www.tomat-pomidor.com\/uploads\/monthly_2021_07\/IMG_20210726_100809.jpg.0987733e32952fe70f73b6aeaeb03788.jpg\" alt=\"Tomato leaf with yellowing and brown spots\" \/><\/p>\n<\/div>\n<\/div>\n<div class=\"forum-post\">\n<div class=\"author-header\">\n<div class=\"forum-avatar\" style=\"background-color: #e91e63; color: white; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 15px; font-size: 1.2em;\">S<\/div>\n<div class=\"author-meta\">\n<div class=\"author-name\">Svetlana-Kr <span class=\"author-stats\">\u2b50 Pro Grower (1,952 posts)<\/span><\/div>\n<div class=\"author-geo\">\ud83d\udccd Zvenigorod, Moscow Reg. (USDA Zone 4b) | \ud83d\udcc5 July 26, 2021<\/div>\n<\/div>\n<\/div>\n<div class=\"post-content\">\n<p>Look who landed on my phlox.<\/p>\n<p><img decoding=\"async\" style=\"max-width: 100%; height: auto; border-radius: 5px; margin: 10px 0;\" src=\"https:\/\/www.tomat-pomidor.com\/uploads\/monthly_2021_07\/IMG_20210726_135136.jpg.8908a4d9b0a4b7f50bf8366efec11fe0.jpg\" alt=\"Insect on a phlox flower\" \/><\/p>\n<\/div>\n<\/div>\n<div class=\"forum-post\">\n<div class=\"author-header\">\n<div class=\"forum-avatar\" style=\"background-color: #3f51b5; color: white; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 15px; font-size: 1.2em;\">M<\/div>\n<div class=\"author-meta\">\n<div class=\"author-name\">MADanilich <span class=\"author-stats\">\u2b50 Veteran Grower (22,092 posts)<\/span><\/div>\n<div class=\"author-geo\">\ud83d\udccd North Tomsk, Siberia (USDA Zone 3a) | \ud83d\udcc5 July 26, 2021<\/div>\n<\/div>\n<\/div>\n<div class=\"post-content\">\n<blockquote><p><strong>Svetlana-Kr wrote:<\/strong><br \/>\nLuda, is this Early Blight (Macrosporiosis) or what? It&#8217;s literally giving me nightmares&#8230;<\/p><\/blockquote>\n<p>Greetings folks! \ud83c\udf1e<\/p>\n<p>Mind if I share a few thoughts here? Of course, the leaf in the photo is pretty far gone and you can&#8217;t fix it, but you CAN prevent this from happening to the new leaves. This applies to nightshades and legumes alike. ALL these fungal blights usually start with CHLOROSIS &#8211; a lack of trace minerals (micronutrients) in a chelated form.<\/p>\n<p>You need to take action the moment you see even a tiny dry edge on the foliage or a slight color change. Chlorosis can evolve FROM a simple nutrient deficiency into a full-blown fungal disease, and that&#8217;s when a gardener goes into panic mode &#8211; what do I do? what disease is this?<\/p>\n<p>A lack of trace minerals usually messes up the photosynthesis process, and the result is obvious&#8230; yellowing and drying of the leaves, especially the older lower ones.<\/p>\n<p>It&#8217;s hard for me to judge the exact cause right now from this photo because it&#8217;s too far gone. If there WAS a photo at the INITIAL STAGE of the disease, I could give specific advice. But I have a lot of practical experience with the causes of chlorosis and its consequences, mostly on tomatoes and potatoes. My conclusion is this: if you can spot it early, a micronutrient deficiency and a fungus look different. But the consequences later on are hard to tell apart because nutrient deficiencies &#8220;pave the way&#8221; for fungal diseases to take over.<\/p>\n<p>In my experience, chlorosis primarily happens from both an excess and a LACK of iron. Sometimes there is plenty of iron in the soil, but the plant just can&#8217;t absorb it&#8230; but in ANY case, the plant will ALWAYS absorb it if you do a foliar spray.<\/p>\n<p>I always keep Iron Chelate in my arsenal. The shelf life is UNLIMITED.<\/p>\n<p>Well, I&#8217;ve talked your ear off here&#8230; plant diseases and fighting them is such a tedious and long topic&#8230;. \ud83d\udc74<\/p>\n<\/div>\n<\/div>\n<div class=\"forum-post\">\n<div class=\"author-header\">\n<div class=\"forum-avatar\" style=\"background-color: #e91e63; color: white; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 15px; font-size: 1.2em;\">S<\/div>\n<div class=\"author-meta\">\n<div class=\"author-name\">Svetlana-Kr <span class=\"author-stats\">\u2b50 Pro Grower (1,952 posts)<\/span><\/div>\n<div class=\"author-geo\">\ud83d\udccd Zvenigorod, Moscow Reg. (USDA Zone 4b) | \ud83d\udcc5 July 26, 2021<\/div>\n<\/div>\n<\/div>\n<div class=\"post-content\">\n<blockquote><p><strong>MADanilich wrote:<\/strong><br \/>\nA lack of trace minerals usually messes up the photosynthesis process&#8230;<\/p><\/blockquote>\n<p>Andrey Danilych, thanks for the wisdom.<\/p>\n<p>I can see my mistakes now:<br \/>\n1. I didn&#8217;t pot up the seedlings into larger containers in time.<br \/>\n2. The roots of this plant were heavily damaged by a shrew. I should have stimulated root growth, but I didn&#8217;t.<br \/>\n3. My watering and feeding was inconsistent. I fed it with a balanced water-soluble fertilizer with micros, but I probably should have used more.<\/p>\n<p>I should probably just pull this tomato plant, but I kept it as an experiment. I treated it with a Copper fungicide today, and I&#8217;ll give it microelements and Iron Chelate.<\/p>\n<\/div>\n<\/div>\n<div class=\"forum-post\">\n<div class=\"author-header\">\n<div class=\"forum-avatar\" style=\"background-color: #4caf50; color: white; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 15px; font-size: 1.2em;\">A<\/div>\n<div class=\"author-meta\">\n<div class=\"author-name\">Aleksan9ra <span class=\"author-stats\">\u2b50 Diary Owner (15,056 posts)<\/span><\/div>\n<div class=\"author-geo\">\ud83d\udccd Moscow Region (USDA Zone 4b) | \ud83d\udcc5 July 26, 2021<\/div>\n<\/div>\n<\/div>\n<div class=\"post-content\">\n<blockquote><p><strong>Svetlana-Kr wrote:<\/strong><br \/>\nLuda, is this Early Blight (Macrosporiosis) or what?<\/p><\/blockquote>\n<p>Sveta, this actually looks more like Anthracnose to me. But the root cause for both of them appearing is exactly the same: planting out too early into cold soil, and as a result, a terribly weak root system.<\/p>\n<\/div>\n<\/div>\n<div class=\"forum-post\">\n<div class=\"author-header\">\n<div class=\"forum-avatar\" style=\"background-color: #3f51b5; color: white; border-radius: 50%; width: 40px; height: 40px; display: flex; align-items: center; justify-content: center; font-weight: bold; margin-right: 15px; font-size: 1.2em;\">M<\/div>\n<div class=\"author-meta\">\n<div class=\"author-name\">MADanilich <span class=\"author-stats\">\u2b50 Veteran Grower (22,092 posts)<\/span><\/div>\n<div class=\"author-geo\">\ud83d\udccd North Tomsk, Siberia (USDA Zone 3a) | \ud83d\udcc5 July 27, 2021<\/div>\n<\/div>\n<\/div>\n<div class=\"post-content\">\n<blockquote><p><strong>Svetlana-Kr wrote:<\/strong><br \/>\nAndrey Danilych, thanks for the wisdom.<\/p><\/blockquote>\n<p>Good morning everyone! \ud83c\udf1e What wisdom!??? It&#8217;s just conclusions based on theory and practice. I just want to pass on SO MUCH to you all, to share my mistakes so you don&#8217;t repeat them.<\/p>\n<p>But I have one golden rule! Many gardening conclusions rely heavily on specific climate conditions and soil parameters. If you don&#8217;t know the climate context, advice turns into useless blah, blah&#8230;<\/p>\n<blockquote><p><strong>Aleksan9ra wrote:<\/strong><br \/>\n&#8230;planting out too early into cold soil, and as a result, a terribly weak root system.<\/p><\/blockquote>\n<p>Ludmilka, I agree with you here 100%%, but&#8230;. YOU MUST understand ONE THING!!!! Roots develop ON COMMAND from the LEAVES&#8230;!!!!! THIS is the chain of dependency for ALMOST any plant development&#8230;.<\/p>\n<p>The leaf is the LANGUAGE of any plant&#8230;.. leaves will tell you EVERYTHING&#8230;..!!&#8230;???&#8230;. \ud83d\udc4b when it&#8217;s happy, and when it&#8217;s stressed&#8230;<\/p>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>\ud83d\udccc Quick Summary: The Tomato Blight Debate \ud83c\udf45 The Standard Advice: When tomato leaves develop yellow halos and dry brown spots, most gardening books say it is a fungal disease (like Early Blight or Anthracnose) and you must reach for fungicides immediately. \ud83e\udd76 Our Community&#8217;s Insight: Veteran growers from cold climates (Zone 3 and 4) &#8230; <a title=\"Brown Tomato Leaf Spots: Fungal Disease vs. Deficiency | Growers Debate\" class=\"read-more\" href=\"https:\/\/www.tomat-pomidor.com\/en\/brown-tomato-leaf-spots-debate\/\" aria-label=\"Read more about Brown Tomato Leaf Spots: Fungal Disease vs. Deficiency | Growers Debate\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":4719,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[472,529],"tags":[],"class_list":["post-4719","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-diseases-weeds","category-growing-tomatoes"],"_links":{"self":[{"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/posts\/4719","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/comments?post=4719"}],"version-history":[{"count":2,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/posts\/4719\/revisions"}],"predecessor-version":[{"id":5034,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/posts\/4719\/revisions\/5034"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/posts\/4719"}],"wp:attachment":[{"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/media?parent=4719"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/categories?post=4719"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tomat-pomidor.com\/en\/wp-json\/wp\/v2\/tags?post=4719"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}